Yes, don’t do it!
I’ve fitted countless of these type of lights in the past within retaining walls. They always end up filling up with moisture and causing problems. IP55 is not enough for the environment it will be subjected to.
In my experience you need to be looking at IP68, which generally means ELV. I normally use Collingwood. Problems are extremely rare and it’s much safer as a bonus.
Don’t be tempted to use SY whatever light fittings you decide upon. It’s not a substitute for SWA and it’s certainly not designed to be used outside as the UV will destroy it (I’ve seen countless AC installs where this has happened).
H07 in ducting is a decent choice if going with ELV
